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Replaces the geometry of the feature with a two-dimensional circular arc whose shape is estimated from the first, middle, and last point of the linear feature passed in. The result is an approximation only and unless the linear feature is previously known to be circular, the result could be completely different than the original feature.

This transformer is most useful when the feature was known to have been a circular arc originally, and was stroked into a line. This transformer can then be used to turn it back into an arc.

For example, a feature containing these points:



    0,2.236067977 (sqrt(5))

will be turned into an arc feature with this geometry:


and these attributes:

    fme_primary_axis     2.236067977

    fme_secondary_axis   2.236067977

    fme_start_angle      26

    fme_sweep_angle      63

    fme_rotation         0

Input Ports

Output Ports


Not applicable.

Usage Notes

If the parameters for the arc are already available as attributes on the feature, then use the 2DArcReplacer or 3DArcReplacer transformer.


Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Transformer Categories


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